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EN
Upper Triassic fossil plants are well documented from the Keuper of Europe. Carnian and Rhaetian floras are rich in a variety of plant taxa, whereas in comparison, the Norian is limited to a few localities with poorly preserved fossil plant communities showing low diversification. The Norian Grabowa Formation in Zawiercie-Marciszów, Upper Silesia, southern Poland, contains fossils of arborescent gymnosperms, including petrified conifer trunks. In this study, we present a fossil plant assemblage, containing fragmented plant parts in multiple forms of preservation, i.e., permineralised trunks and rooting structures, stems compressions, dispersed cuticles, and megaspores. Analysis of the macromorphological characters proved the presence of gymnosperms, including the ar-borescent conifer Agathoxylon cf. keuperianum, known already from this locality from fragments of charcoalified wood. Sphenophytes are represented by disarticulated stems of Equisetites sp., and Neocalamites sp. The variation in plant fossils indicates the possibility of higher plant diversity. Analysis of cuticles, macerated from different plant-bearing lithologies, revealed a variety of conifer foliage, expressed as five cuticulae dispersae morphotypes (needle-leaf Elatocladus-type and scale-leaf Pagio- Brachyphyllum-like). Plant fossils at Zawiercie-Marciszów are preserved in calcareous mudstones and micritic limestone concretions, developed in a fluvial environment. The presence of sphenophyte stems (Equisetites and Neocalamites) indicates that local conditions were more humid and suitable for spore-producing plants, appearing in the mid-Norian tectonic-pluvial episode, recorded in the Grabowa Fm.
EN
Dispersed miospore and pollen assemblages are described from the Radnice Basin, Middle Pennsylvanian, Czech Republic. Conversion factors (R-values) were produced by comparing the palynological data with quantified macrofloral data, to relate the percentages of spore/pollen taxa to those of the major plant groups that produced them. Among arborescent lycopsids, the miospore and macroplant counts are more or less equal. In other lycopsids miospores are strongly over-represented, as their macroplant remains were relatively fewer than would be suggested by the proportion of their spores in miospore spectra. Sphenophyll and calamitid macroplants were also relatively fewer than are their spores as a proportion of palynological spectra. By contrast, macroplants of ferns and cordaites are relatively more numerous than are their miospores and pollen in palynological spectra.
EN
Hydrophilic elements, such as sphenopsids and fems, are rare in the flora of the Krasiejów site and they are poorly preserved. One sphenopsid species, Neocalamites merianii, was recognised. It is preserved as impressions, flattened casts, moulds and isolated leaves. So far, only one small fern specimen, determined as Sphenopteris sp., has been found. These elements probably were transported to the site of deposition and did not grow where they were buried.
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